gcc/gimple-streamer-out.c

   1 /* Routines for emitting GIMPLE to a file stream.
   2
   3    Copyright (C) 2011-2021 Free Software Foundation, Inc.
   4    Contributed by Diego Novillo <dnovillo@google.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "backend.h"
  26 #include "tree.h"
  27 #include "gimple.h"
  28 #include "gimple-ssa.h"
  29 #include "gimple-streamer.h"
  30 #include "tree-eh.h"
  31 #include "gimple-iterator.h"
  32 #include "cgraph.h"
  33 #include "value-prof.h"
  34 #include "gimple-pretty-print.h"
  35
  36 /* Output PHI function PHI to the main stream in OB.  */
  37
  38 static void
  39 output_phi (struct output_block *ob, gphi *phi)
  40 {
  41   unsigned i, len = gimple_phi_num_args (phi);
  42
  43   streamer_write_record_start (ob, lto_gimple_code_to_tag (GIMPLE_PHI));
  44   streamer_write_uhwi (ob, SSA_NAME_VERSION (PHI_RESULT (phi)));
  45
  46   for (i = 0; i < len; i++)
  47     {
  48       stream_write_tree (ob, gimple_phi_arg_def (phi, i), true);
  49       streamer_write_uhwi (ob, gimple_phi_arg_edge (phi, i)->src->index);
  50       bitpack_d bp = bitpack_create (ob->main_stream);
  51       location_t loc = gimple_phi_arg_location (phi, i);
  52       stream_output_location_and_block (ob, &bp, loc);
  53     }
  54 }
  55
  56
  57 /* Emit statement STMT on the main stream of output block OB.  */
  58
  59 static void
  60 output_gimple_stmt (struct output_block *ob, struct function *fn, gimple *stmt)
  61 {
  62   unsigned i;
  63   enum gimple_code code;
  64   enum LTO_tags tag;
  65   struct bitpack_d bp;
  66   histogram_value hist;
  67
  68   /* Emit identifying tag.  */
  69   code = gimple_code (stmt);
  70   tag = lto_gimple_code_to_tag (code);
  71   streamer_write_record_start (ob, tag);
  72
  73   /* Emit the tuple header.  */
  74   bp = bitpack_create (ob->main_stream);
  75   bp_pack_var_len_unsigned (&bp, gimple_num_ops (stmt));
  76   bp_pack_value (&bp, gimple_no_warning_p (stmt), 1);
  77   if (is_gimple_assign (stmt))
  78     bp_pack_value (&bp,
  79                    gimple_assign_nontemporal_move_p (
  80                      as_a <gassign *> (stmt)),
  81                    1);
  82   bp_pack_value (&bp, gimple_has_volatile_ops (stmt), 1);
  83   hist = gimple_histogram_value (fn, stmt);
  84   bp_pack_value (&bp, hist != NULL, 1);
  85   bp_pack_var_len_unsigned (&bp, stmt->subcode);
  86
  87   /* Emit location information for the statement, including gimple_block.  */
  88   stream_output_location_and_block (ob, &bp, gimple_location (stmt));
  89
  90   /* Emit the operands.  */
  91   switch (gimple_code (stmt))
  92     {
  93     case GIMPLE_RESX:
  94       streamer_write_hwi (ob, gimple_resx_region (as_a <gresx *> (stmt)));
  95       break;
  96
  97     case GIMPLE_EH_MUST_NOT_THROW:
  98       stream_write_tree (ob,
  99                          gimple_eh_must_not_throw_fndecl (
 100                            as_a <geh_mnt *> (stmt)),
 101                          true);
 102       break;
 103
 104     case GIMPLE_EH_DISPATCH:
 105       streamer_write_hwi (ob,
 106                           gimple_eh_dispatch_region (
 107                             as_a <geh_dispatch *> (stmt)));
 108       break;
 109
 110     case GIMPLE_ASM:
 111       {
 112         gasm *asm_stmt = as_a <gasm *> (stmt);
 113         streamer_write_uhwi (ob, gimple_asm_ninputs (asm_stmt));
 114         streamer_write_uhwi (ob, gimple_asm_noutputs (asm_stmt));
 115         streamer_write_uhwi (ob, gimple_asm_nclobbers (asm_stmt));
 116         streamer_write_uhwi (ob, gimple_asm_nlabels (asm_stmt));
 117         streamer_write_string (ob, ob->main_stream,
 118                                gimple_asm_string (asm_stmt), true);
 119       }
 120       /* Fallthru  */
 121
 122     case GIMPLE_ASSIGN:
 123     case GIMPLE_CALL:
 124     case GIMPLE_RETURN:
 125     case GIMPLE_SWITCH:
 126     case GIMPLE_LABEL:
 127     case GIMPLE_COND:
 128     case GIMPLE_GOTO:
 129     case GIMPLE_DEBUG:
 130       for (i = 0; i < gimple_num_ops (stmt); i++)
 131         {
 132           tree op = gimple_op (stmt, i);
 133           tree *basep = NULL;
 134           /* Wrap all uses of non-automatic variables inside MEM_REFs
 135              so that we do not have to deal with type mismatches on
 136              merged symbols during IL read in.  The first operand
 137              of GIMPLE_DEBUG must be a decl, not MEM_REF, though.  */
 138           if (!flag_wpa && op && (i || !is_gimple_debug (stmt)))
 139             {
 140               basep = &op;
 141               if (TREE_CODE (*basep) == ADDR_EXPR)
 142                 basep = &TREE_OPERAND (*basep, 0);
 143               while (handled_component_p (*basep))
 144                 basep = &TREE_OPERAND (*basep, 0);
 145               if (VAR_P (*basep)
 146                   && !auto_var_in_fn_p (*basep, fn->decl)
 147                   && !DECL_REGISTER (*basep))
 148                 {
 149                   bool volatilep = TREE_THIS_VOLATILE (*basep);
 150                   tree ptrtype = build_pointer_type (TREE_TYPE (*basep));
 151                   *basep = build2 (MEM_REF, TREE_TYPE (*basep),
 152                                    build1 (ADDR_EXPR, ptrtype, *basep),
 153                                    build_int_cst (ptrtype, 0));
 154                   TREE_THIS_VOLATILE (*basep) = volatilep;
 155                 }
 156               else
 157                 basep = NULL;
 158             }
 159           stream_write_tree (ob, op, true);
 160           /* Restore the original base if we wrapped it inside a MEM_REF.  */
 161           if (basep)
 162             *basep = TREE_OPERAND (TREE_OPERAND (*basep, 0), 0);
 163         }
 164       if (is_gimple_call (stmt))
 165         {
 166           if (gimple_call_internal_p (stmt))
 167             streamer_write_enum (ob->main_stream, internal_fn,
 168                                  IFN_LAST, gimple_call_internal_fn (stmt));
 169           else
 170             stream_write_tree (ob, gimple_call_fntype (stmt), true);
 171         }
 172       break;
 173
 174     case GIMPLE_NOP:
 175     case GIMPLE_PREDICT:
 176       break;
 177
 178     case GIMPLE_TRANSACTION:
 179       {
 180         gtransaction *txn = as_a <gtransaction *> (stmt);
 181         gcc_assert (gimple_transaction_body (txn) == NULL);
 182         stream_write_tree (ob, gimple_transaction_label_norm (txn), true);
 183         stream_write_tree (ob, gimple_transaction_label_uninst (txn), true);
 184         stream_write_tree (ob, gimple_transaction_label_over (txn), true);
 185       }
 186       break;
 187
 188     default:
 189       gcc_unreachable ();
 190     }
 191   if (hist)
 192     stream_out_histogram_value (ob, hist);
 193 }
 194
 195
 196 /* Output a basic block BB to the main stream in OB for this FN.  */
 197
 198 void
 199 output_bb (struct output_block *ob, basic_block bb, struct function *fn)
 200 {
 201   gimple_stmt_iterator bsi = gsi_start_bb (bb);
 202
 203   streamer_write_record_start (ob,
 204                                (!gsi_end_p (bsi)) || phi_nodes (bb)
 205                                 ? LTO_bb1
 206                                 : LTO_bb0);
 207
 208   streamer_write_uhwi (ob, bb->index);
 209   bb->count.stream_out (ob);
 210   streamer_write_hwi (ob, bb->flags);
 211   streamer_write_hwi (ob, bb->discriminator);
 212
 213   if (!gsi_end_p (bsi) || phi_nodes (bb))
 214     {
 215       /* Output the statements.  The list of statements is terminated
 216          with a zero.  */
 217       for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi))
 218         {
 219           int region;
 220           gimple *stmt = gsi_stmt (bsi);
 221           if (streamer_dump_file)
 222             {
 223               fprintf (streamer_dump_file, "  Streaming gimple stmt ");
 224               print_gimple_stmt (streamer_dump_file, stmt, 0, TDF_SLIM);
 225             }
 226
 227           output_gimple_stmt (ob, fn, stmt);
 228
 229           /* Emit the EH region holding STMT.  */
 230           region = lookup_stmt_eh_lp_fn (fn, stmt);
 231           if (region != 0)
 232             {
 233               streamer_write_record_start (ob, LTO_eh_region);
 234               streamer_write_hwi (ob, region);
 235             }
 236           else
 237             streamer_write_record_start (ob, LTO_null);
 238         }
 239
 240       streamer_write_record_start (ob, LTO_null);
 241
 242       for (gphi_iterator psi = gsi_start_phis (bb);
 243            !gsi_end_p (psi);
 244            gsi_next (&psi))
 245         {
 246           gphi *phi = psi.phi ();
 247
 248           /* Only emit PHIs for gimple registers.  PHI nodes for .MEM
 249              will be filled in on reading when the SSA form is
 250              updated.  */
 251           if (!virtual_operand_p (gimple_phi_result (phi)))
 252             output_phi (ob, phi);
 253         }
 254
 255       streamer_write_record_start (ob, LTO_null);
 256     }
 257 }